Roof mounted solar panel - 2004 Roadtrek 190 V C

[cruisefx]

We are planning on installing a 250w solar panel on the roof of our 2004 Roadtrek 190 Versatile. It will extend back from the fantastic fan to the end of the roof.

While researching, I found many different suggestions for attaching the panel to the roof. One is to use "Sticky Feet" aluminum brackets which have 3M VHB tape attached to the bottoms. I'd like to know how secure a solution this would this be, does anyone have knowledge of using this method ?

Also suggested, is using well nuts to attach brackets after drilling through the fibreglass. With this approach it would be extremely helpful to know where not to drill. Are there any schematics showing existing wire routings etc. just below the roof ?

I'd like to know where the two roll-over metal hoops are located, so that I could consider using a well nut through a drilled hole in the metal hoop, for what would seem a solid spot to attach brackets.
Advice appreciated.

[booster]

This is how we did ours on our 07 Chevy 190P.

http://classbforum.com/phpBB2/viewtopic.php?f=12&t=2414

Sounds like you are going to do similar, but with a single panel. Your 04 doesn't have the antenna to avoid, I think, so one big panel would fit better than on ours. If we didn't have the antenna, we could have fit 3 of the 100 watt panels on ours.

We used well nuts, the type with the split collapsing section, as the fiberglass is not uniform in thickness or flat on the inside. When I put the brackets onto the well nuts, I set them into urethane caulking also, for more hold and sealing. It has held up well.

I looked for quite a while trying to find any recommended drilling area, but never found anything official. I don't think it is necessary to hit the hoops, I would be more concerned with getting a nice flat layout of the panel, with the supports in areas recommended by the panel manufacturer.

[cruisefx]

Thanks for the info booster. Yes, we are fortunate in this situation not to have an antenna.
Interesting that the fibreglass is not a uniform thickness or flat inside - good to know.

So, urethane caulking rather than the silicone self leveling stuff.
I'll be sure to check with the manufacturer for the panel support areas.

[booster]

We like the urethane caulking better than silicone, and I used it to reseal the toilet vent and Fantastic fan also. It seems to be stickier, with less chance of coming off, plus if you get a gap in the future, it will stick to itself, which silicone doesn't do very well. I don't remember the brand that many of the solar installers use, but it think it is urethane also (self leveling). I used regular for a lot of the install, and a little self leveling where it worked better. Another plus is that you can paint the urethane if you chose to.

[cruisefx]

Finally got around to writing about how things turned out with the installation.
You can read and see it here:
https://www.dropbox.com/s/uhthovd1xu...ravel.pdf?dl=0

[stanw909]

I just installed a solar panel using only Eterna Bond. So far it's looking good and has weathered very strong cross winds in the desert driving home from Joshua Tree. I do admit that I was very nervous the first time I got on the freeway, but after a couple of weeks of driving around in variuos conditions I think it's going to be a success with no holes drilled in the roof.

[stanw909]

Excellant tutorial BTW

[markopolo]

Yes, great tutorial. Looks like a good install to me & nice high quality brand components.

That was a brilliant idea to use the basically unused automatic transfer switch

Are you going to utilize the two outside battery compartments?

Maybe you could add a relay with a switch to allow you to use the isolator if ever needed.

[booster]

Very nice writeup!

I am having a bit of a problem understanding the transfer switch wiring. How do you keep the inverter from running the shore charger when you are inverting to all the outlets at the transfer switch. I think our shore charger is powered from the main panel on our 07.

[cruisefx]

We currently have the old coach battery in it's original location, fully charged as a backup. Manual connection required at the moment if needed. It's off the circuit currently, since it is of a different type to the two new solar charged batteries. A relay with switch for the isolator sounds like a good idea Markopolo.

Turns out it was rather simple to prevent the inverter from running the shore charger. I just don't turn on the disconnect battery switch.

[booster]

Where did you locate the battery disconnect switch? Do you lose the 12v power to the coach when you do?

[booster]

I just looked at the wiring diagrams for the 2004 190s and I think I answered my own question.

You shore charger goes on the load side of the 12v power relay, so it is not connected directly to the batteries like the newer models (I think it changed when they went to separators). Our 2007 with a separator has the shore charger connected to the battery side, so the relay wouldn't disconnect it, and the charger/inverter would loop.

I would think that the charger is running, however, as it should be getting 110 volt power from the inverter. It would also be running the 12v side to the coach, if it will initiate without seeing a battery. Obviously, this has not been a big enough load to interfere with what you need to do with inverter.

It also means that you have one of the units that require the 12v relay to be on when you plug into shore power if you want the batteries to charge. I don't know if it runs the coach at that point.